Medieval Bolesławiec was above all a trading town. Markets were held here as early as the turn of the 12th and 13th centuries, and also in the following years. Existing sources attest to the presence of a land-based, ducal customs chamber in Bolesławiec even before 1251, that is, before the town was founded under German town law. The town’s location on important trade routes was put to use: from Wrocław to Leipzig, from Wrocław to Lwówek and onward to Jelenia Góra and Prague, as well as from Szprotawa to Lwówek Śląski. The ducal customs chamber existed until 1330; customs duties were collected at the town gates. Bolesławiec merchants maintained lively relations with the rest of the Polish lands. They imported tallow and wool and exported cloth. During the Piast era, the town was the largest salt market in Silesia. Trade therefore determined the growing wealth of the townspeople. Merchants also belonged to the town’s wealthiest citizens.
Alongside trade, weaving also played a significant role. In the 14th century, Bolesławiec had a cloth-makers’ guild. In the mid-16th century, around 700 people were engaged in cloth-making (the town had approximately 3,000 inhabitants). The Thirty Years’ War (1618–1648) caused weavers to leave the town en masse. They moved to Greater Poland, Lusatia and Brandenburg. After the war ended, only a few returned to Bolesławiec. Blacksmithing and locksmithing crafts played an important role. In 1404, among the four town councillors (a group of the wealthiest inhabitants) were two metal craftsmen—a blacksmith and a sword-maker. In 1563, there were already four blacksmiths and one locksmith. The Thirty Years’ War halted the development of crafts, and only between 1650 and 1700 did the number of craftsmen in these specialities increase substantially. In 1655, the blacksmiths even had their own guild. From the 14th century, Bolesławiec residents derived considerable profits from brewing beer. Brewing privileges were confirmed by every monarch ascending the throne. Bolesławiec beer was famous for its taste. It was served as a beverage during luxurious banquets at the castle.
On several occasions, it saved the town from its enemies, when in 1427, 1469 and 1629 it was used as a ransom demanded by besieging armies.
From the 14th century, pottery workshops were established in Bolesławiec, drawing on rich deposits of ceramic clay located near the town. The potters’ guild was small, and its members were not very wealthy, since the 1563 register of Bolesławiec residents—which listed house owners and the amount of weaponry they possessed—does not mention potters. The Thirty Years’ War brought about the destruction of the existing workshops. It was only from the second half of the 17th century that a gradual development of ceramic production can be observed.
The sources of the town’s wealth were therefore diverse; however, trade was decisive for the town’s development. It was also the primary factor behind the town’s growth.